CD40LG and cystic fibrosis: We describe a case of dengue in a lung transplant recipient which manifested predominantly as ocular symptoms following short-lived systemic features, and with protracted viraemia with delayed IgM to IgG seroconversion.<h4>Case presentation</h4>A 40-year-old woman who had a bilateral lung transplant 15 years prior for cystic fibrosis presented with headaches, bilateral scotomata and rapidly deteriorating visual acuity.